Rail bosses will today launch a study looking at the possibility of building five new high-speed lines in Britain to cope with increasing passenger demand.

Rail infrastructure company Network Rail said it would be conducting a strategic review for building new lines along some of the UK's busiest routes in what would amount to the largest track build since the 19th century.

More than one million people travelled by train last year, the highest number since the Second World War demob year of 1946, and growth is predicted to swell by 30% in the next decade.

Network Rail plans to build five new lines in the biggest track build since the 19th century

Network Rail plans to build five new lines in the biggest track build since the 19th century

Network Rail revealed yesterday that consultants will be appointed by the end of July and the first report into the possibility of building new lines is expected by next summer.

The company said it would be looking at five routes of the busiest routes in the country - Chiltern, East Coast, West Coast, Great Western and Midland Main Line.

Network Rail chief executive Iain Coucher said: "By 2025 many lines will be full-up, especially those running to and from the north and west of London. This will happen even after we have implemented the investment to boost current capacity.

"With popularity for rail growing, we have to start planning for the medium and long-term future today. We have to see how we can meet the capacity challenge and see what solutions - including potentially, that of new lines - are deliverable and affordable.

"This review, working in partnership with other players in the railway industry, will kick-start this process."

Mr Coucher went on: "We are uniquely positioned to take a network-whole approach in planning the railway of the future. We have a thriving railway today and that must continue and grow to meet the economic and environmental needs of tomorrow's Great Britain."

It is likely that most, if not all, of any new lines will be high speed in what would amount to the largest track building programme since the 19th century.

The study will also look at the benefits to the UK economy of increased rail travel, especially in the light of rising oil prices.

The Rail, Maritime and Transport Union yesterday welcomed the move and said environmental pressures dictated that new high-speed railway lines, as well as electrification of existing lines but be made sooner rather than later.

Bob Crow, the union's general secretary, said: "The future lies in high-speed rail and electrification of the existing network, because the environment and the economy are crying out for a decisive shift away from never-ending expansion of road and air travel and because the oil crisis is not going to go away."

In the last decade passenger numbers have soared by 40%, with 1.13 billion journeys a year now being made - the greatest number since 1946 when the network was twice the size.

Today around 22,000 services run on weekdays - up from 17,000 at the time of privatisation. In that time too, the amount of freight carried has rocketed by 60%.

Network Rail said today that all credible current projections point to similar growth over the next decade. And punctuality has improved to a point where 90% of services arrive on time.

Network Rail said it had launched a tendering process to appoint a consultancy to assist its new-line study.